Year	Number of
1990	5669.56
1991	5925.09
1992	6190.83
1993	6470.48
1994	6768.91
1995	7094.19
1996	7411.77
1997	7761.95
1998	8152.15
1999	8571.42
2000	9022
2001	9391.69
2002	9784.9
2003	10207.81
2004	10635.68
2005	11071.13
2006	11437.78
2007	11793.94
2008	12174.69
2009	12579.99
2010	13025.96
2011	13420.22
2012	13846.89
2013	14290.93
2014	14748.39
2015	15214.46
2016	15679.81